Test Research On Catastrophe Characteristics And Initiation Mechanism Of Debris-flows In Taihang Mountainous Areas

According to the grain size of debris-flow soil in Taihang mountain area of Hebeiprovince, it is gravel soil with wide grain size, the gravelly grain content is large, theinitiation of debris-flow is obviously impacted by the gravelly grain content. Theimpact study on soil graduation against debris-flow initiation has a great significanceto explore the activated mechanism of debris-flows.The present studies by domestic experts and scholars on the debris flow areconcentrated in Southwest China, and less in North China. The debris flow inSouthwest China mostly belong to the general debris flow, it has a wide particle sizedistribution and a higher content of fine particles. But in North China, especially in theTaihang Mountains, the debris flow is a water-rock flow, it has a wide particle sizedistribution, a higher content of gravelly grain, a high shock potential energy and alarge destructive power. So the study on debris flow in Taihang Mountains conduce tothe study on the disaster characteristics of water-rock flow and the activatedmechanism.In this paper, there used the soil box model tests to study debris-flow phenomenain a variety of experimental conditions, and recorded under the experimentalphenomena and data analysis as a basis to explore the initiation mechanism of thedebris-flow. Summary, by analyzing and comparing the experimental phenomena andtest data, reasonable explanation of some phenomenon in the debris-flow process, helpto further improve understanding of the initiation mechanism of debris-flow. The mainresults obtained in the following areas:1.Through a comprehensive analysis of several typical debris flow in the TaihangMountain which is in the west of Handan, by combing with the the influence ofgeology, landform, climate, hydrology, soil and vegetation, as well as human activityinfluence in the study area, summarizes the main characteristics of debris flowformation.2.Through the indoor model tests of the debris flow under the action of runoff, analysethe initiation and formation process of debris flow under the action of runoff, and studythe relationship between each main control factors of debris flow under the action ofthe runoff.3.Through the indoor model tests of the debris flow under the action of runoff and rainfall, analyse the initiation and formation process of debris flow under the conditionof rainfall, and study the relationship between each main control factors of debris flowunder the condition of rainfall.4.By analysing the initiation and failure form of debris flow,it has certain referencevalue to the further research about the disaster characteristics of debris flow in theTaihang mountains.5.By analysing the initiation of debris flow, it improve the study about the mechanismof debris flow in Taihang mountain.